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Search indexed NASA NTRS and DOE OSTI research on propulsion, heat transfer, battery materials and energy systems. Follow report and document links to the original sources.

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At least 199 records · Page 11
All sourcesNASA NTRSDOE OSTI
NASA NTRS2017

Enabling Autonomous Space Mission Operations with Artificial Intelligence

For over 50 years, NASA's crewed missions have been confined to the Earth-Moon system, where speed-of-light communications delays between crew and ground are practically nonexistent. This ground-centered mode of operations, with a large, ground-based support team, is not sustainable for NASAs future human exploration missions to Mars. Future astronauts will need smarter tools employing Artificial Intelligence (AI) techniques make decisions without inefficient communication back and forth with ground-based mission control. In this talk we will describe several demonstrations of astronaut decision support tools using AI techniques as a foundation. These demonstrations show that astronauts tasks ranging from living and working to piloting can benefit from AI technology development.

Frank, Jeremy↗
NASA NTRSDate not supplied

Developing Wear-Resistant Coatings for Lunar Dust Tolerant Applications

Materials resistant to the harsh lunar environment are needed to support long duration, sustainable missions on the Moon’s surface. Lunar dust poses a significant threat to the durability of components and vehicles due to its fine, jagged morphology and highly abrasive nature. These properties result in particles eroding, adhering and/or embedding onto component surfaces and into device confined geometries (e.g., gear housing, interlocking systems, etc.) potentially leading to premature failure. The aim of this work is to identify and characterize wear-resistant materials for use as protective coatings to minimize abrasion caused by lunar dust.Concurrently, testing and evaluation methods will be devised to elucidate and mimic aspects of lunar dust degradation, including particle embedding, gouging and erosion caused by high velocity impact events. Discussion on balancing the need for dust management and tolerance versus dust adhesion mitigation will be shared in context of relevant lunar applications within the NASA Lunar Occupancy Dust Surface Separation Technologies (LO-DuSST) effort, which is part of a NASA-wide effort to enable a sustained lunar presence through the Lunar Surface Innovation Initiative (LSII).

Materials, Coatings, lunar dust management/mitigat↗
NASA NTRSDate not supplied

Modeling Provider Creativity in Medical System Design Simulating a Medical MacGyver

This presentation describes a method for modeling provider creativity during the requirements building and risk assessment phase of medical system design. Practicing medicine in isolated, confined, and extreme environments requires providers to use limited supplies in creative ways. This is necessary to handle unexpected medical events or make better use of limited storage capacity by leaving low-use, bulky equipment behind in favor of in situ or dual-use resources. This is a highly-valued skillset in remote environments, however, the ability to simulate this care creativity computationally is difficult.

Brian Lonquich↗
NASA NTRSDate not supplied

Protective Coatings for Mitigating Lunar Dust Abrasion and Adhesion

Materials resistant to the harsh lunar environment are needed to support long duration, sustainable missions on the Moon’s surface. Lunar dust poses a significant threat to the durability of components and vehicles due to its fine, jagged morphology and highly abrasive nature. These characteristics result in particles eroding, adhering and/or embedding onto component surfaces and into device confined geometries (e.g., gear housing, interlocking systems, etc.) potentially leading to premature failure. The aim of this work is to identify and characterize wear-resistant materials, including advanced ceramics, for use as protective coatings to minimize abrasion and adhesion caused by lunar dust. Results from testing and evaluation methods devised to elucidate and mimic aspects of lunar dust degradation, including adhesion, abrasion and erosion, as well as the lunar environment, will be presented. Discussion on balancing the need for dust management and tolerance versus dust adhesion mitigation will be shared in context of relevant lunar applications within the NASA Lunar Occupancy Dust Surface Separation Technologies effort, which is part of a NASA-wide effort to enable a sustained lunar presence through the Lunar Surface Innovation Initiative.

lunar dust mitigation↗
NASA NTRS2023

Protective Coatings for Lunar Dust Tolerance

Materials capable of withstanding the harsh lunar environment are critically needed to support long duration, sustainable missions on the Moon’s surface. Lunar dust significantly threatens the durability and reusability of components and vehicles due to possessing a fine, jagged morphology and highly abrasive nature. These characteristics result in the particles eroding, adhering and/or embedding onto component surfaces and into device confined geometries (e.g., gear housing, interlocking systems, etc.) potentially leading to premature failure. The aim of this study is to identify and characterize wear-resistant commercial-off-the-shelf (COTS) materials, including advanced ceramics, for use as protective coatings to minimize abrasion and adhesion caused by lunar dust. Preliminary testing that mimics various aspects of lunar dust degradation, such as abrasive wear and adhesion, suggests that COTS ceramic coatings can improve lunar dust tolerance and protect underlying metallic substrates.

Valerie. L. Wiesner↗
NASA NTRS1991

An inertial fusion propulsion scheme for solar system exploration

The paper analyzes a novel fusion scheme that combines the favorable aspects of both inertial and magnetic confinement approaches as a propulsion device for potential application in solar system exploration. An appropriate set of equations for the plasma dynamics and the magnetic nozzle is used to assess the system's propulsive capability by applying the results to a round trip mission to Mars. It is found that such a device would allow a massive vehicle to make the journey in less than five months. It is shown that catalyzed deuterium-deuterium fuel results in a somewhat poorer propulsion performance than deuterium-tritium though at a significantly lower neutron production. The velocity increment generated by this system and the corresponding trip time are in excellent agreement with the predictions of Irving and Blum (1959).

Kammash, Terry↗
NASA NTRS1982

Plasma shocks and energetic particles in the outer solar system - Trapping and asymmetry observations from Pioneer 10 and Pioneer 11

The April 15 and 28, 1978 solar flares appear to have 0.5-20 MeV protons trapped between a pair of shocks, and the large count rate enhancement observed, along with large ranges of radial distance and longitudinal angles, imply a prolongation of trapping for a period of weeks. The apparent ability of a shock whose plasma signature is faint to confine MeV protons in the outer solar system may have significant implications for cosmic ray studies. Analytical results also imply significant azimuthal asymmetry in plasma and energetic particle behavior, at distances as far as 16 AU from the sun. Combining these observations provides evidence for unexpectedly complex interactions in the outer solar system between energetic particles and solar wind plasma.

Intriligator, D. S.↗
NASA NTRS1973

Structural and lithologic study of northern coast ranges and Sacramento Valley, California

The author has identified the following significant results. Analysis of ERTS-1 imagery of the Northern California Coast Ranges has disclosed a potential relation between a heretofore unrecognized fracture system and known deposits of mercury and geothermally active areas in the Coast Range and between oil and gas fields in the Sacramento Valley. Three potentially important systems of linear elements within the Coast Ranges, detected on ERTS-1 imagery, may represent fault systems or zones of shearing because topographic offset and stratigraph disruption can be seen along one or two of the lineations. One of the systems in subparallel to the San Andreas fault and is confined to the Pacific Coastal Belt. Another set is confined to the central core of the Coast Ranges. The third set of linear features (Valley System) has not heretofore been recognized. Some of the known mercury deposits and geothermally active areas near Clear Lake, in the Coast Ranges, are along the Valley System or at the intersection of the Central and Valley Systems. The plotted locations of some of the oil and gas fields in the Sacramento Valley are associated with the Valley and/or Central Systems. If these relations prove reliable, the ERTS-1 imagery may prove to be an extremely useful exploration tool.

Rich, E. I.↗
NASA NTRS1985

Satellite voice broadcast system study, volume 2

This study investigates the feasibility of providing Voice of America (VOA) broadcasts by satellite relay, rather than via terrestrial relay stations. Satellite voice broadcast systems are described for three different frequency bands: HF (26 MHz), VHF (68 MHz), and L-band (1.5 GHz). The geographical areas of interest at HF and L-band include all major land masses worldwide with the exception of the U.S., Canada, and Australia. Geostationary satellite configurations are considered for both frequency bands. In addition, a system of subsynchronous, circular satellites with an orbit period of 8 hours is developed for the HF band. VHF broadcasts, which are confined to the Soviet Union, are provied by a system of Molniya satellites. Satellites intended for HF or VHF broadcastinbg are extremely large and heavy. Satellite designs presented here are limited in size and weight to the capability of the STS/Centaur launch vehicle combination. Even so, at HF it would take 47 geostationary satellites or 20 satellites in 8-hour orbits to fully satisfy the voice-channel requirements of the broadcast schedule provided by VOA. On the other hand, three Molniya satellites suffice for the geographically restricted schedule at VHF. At L-band, only four geostationary satellites are needed to meet the requirements of the complete broadcast schedule. Moreover, these satellites are comparable in size and weight to current satellites designed for direct broadcast of video program material.

Horstein, M.↗
NASA NTRS2015

Marshall Space Flight Center Faculty Fellowship Program

The Faculty Fellowship program was revived in the summer of 2015 at NASA Marshall Space Flight Center, following a period of diminished faculty research activity here since 2006 when budget cuts in the Headquarters' Education Office required realignment. Several senior Marshall managers recognized the need to involve the Nation's academic research talent in NASA's missions and projects to the benefit of both entities. These managers invested their funds required to establish the renewed Faculty Fellowship program in 2015, a 10-week residential research involvement of 16 faculty in the laboratories and offices at Marshall. These faculty engineers and scientists worked with NASA collaborators on NASA projects, bringing new perspectives and solutions to bear. This Technical Memorandum is a compilation of the research reports of the 2015 Marshall Faculty Fellowship program, along with the Program Announcement (appendix A) and the Program Description (appendix B). The research touched on seven areas-propulsion, materials, instrumentation, fluid dynamics, human factors, control systems, and astrophysics. The propulsion studies included green propellants, gas bubble dynamics, and simulations of fluid and thermal transients. The materials investigations involved sandwich structures in composites, plug and friction stir welding, and additive manufacturing, including both strength characterization and thermosets curing in space. The instrumentation projects involved spectral interfero- metry, emissivity, and strain sensing in structures. The fluid dynamics project studied the water hammer effect. The human factors project investigated the requirements for close proximity operations in confined spaces. Another team proposed a controls system for small launch vehicles, while in astrophysics, one faculty researcher estimated the practicality of weather modification by blocking the Sun's insolation, and another found evidence in satellite data of the detection of a warm-hot intergalactic medium filament. Our goal is to continue the Faculty Fellowship effort with Center funds in succeeding summers.

Six, N. F.↗
NASA NTRS1972

Design and testing of a magnetic suspension and damping system for a space telescope

The basic equations of motion are derived for a two dimensional, three degree of freedom simulation of a space telescope coupled to a spacecraft by means of a magnetic suspension and isolation system. The system consists of paramagnetic or ferromagnetic discs confined to the magnetic field between two Helmholtz coils. Damping is introduced by varying the magnetic field in proportion to a velocity signal derived from the telescope. The equations of motion are nonlinear, similar in behavior to the one-dimensional Van der Pol equation. The computer simulation was verified by testing a 264-kilogram air bearing platform which simulates the telescope in a frictionless environment. The simulation demonstrated effective isolation capabilities for disturbance frequencies above resonance. Damping in the system improved the response near resonance and prevented the build-up of large oscillatory amplitudes.

Ockman, N. J.↗
NASA NTRS1994

VSTOL Systems Research Aircraft (VSRA) Harrier

NASA's Ames Research Center has developed and is testing a new integrated flight and propulsion control system that will help pilots land aircraft in adverse weather conditions and in small confined ares (such as, on a small ship or flight deck). The system is being tested in the V/STOL (Vertical/Short Takeoff and Landing) Systems research Aircraft (VSRA), which is a modified version of the U.S. Marine Corps's AV-8B Harrier jet fighter, which can take off and land vertically. The new automated flight control system features both head-up and panel-mounted computer displays and also automatically integrates control of the aircraft's thrust and thrust vector control, thereby reducing the pilot's workload and help stabilize the aircraft for landing. Visiting pilots will be encouraged to test the new system and provide formal evaluation flights data and feedback. An actual flight test and the display panel of control system are shown in this video.

Source record↗
NASA NTRS1982

Air jet levitation furnace system for observing glass microspheres during heating and melting

A collimated hole structure air jet levitation system has been developed which can be used to levitate hollow glass microspheres used in inertial confinement fusion studies. An ellipsoidal furnace has been added to the system to provide a heating source. A video camera and a 16 mm movie camera connected to a microsphere system provide real time observation as well as permanent documentation of the experiments. Microspheres have been levitated at temperatures over 1400 C for over 10 minutes at a time.

Ethridge, E. C.↗
DOE OSTI2025

Experimental analysis of gas dynamics in the reactor cavity section of a High-Temperature Gas-Cooled Reactor during an accident scenario

Here, this study investigates the behavior of a High-Temperature Gas-Cooled Reactor (HTGR) during a break of the helium pressure boundary event. Understanding the gas dynamics that occur during a break could help develop safety systems that reduce the probability of air entering the reactor core. To achieve this objective, experimental studies were conducted in a scaled-down HTGR experimental facility to provide information on the air-helium gas mixture within the confinement building and the impact of the ventilation system on the helium/air gas concentration following the depressurization event. The study evaluated different configurations, including active ventilation time scales, break sizes, and locations. The analysis of the active ventilation time revealed that a ventilation time of 22 seconds produced positive results, and smaller break sizes resulted in longer depressurization times, which improved the ventilation process. The orientation and elevation of the breaks had little effect on the oxygen concentration in the cavity but did impact the gas velocities.

22 - GENERAL STUDIES OF NUCLEAR REACTORS↗
NASA NTRS1993

Curved grating fabrication techniques for concentric-circle grating, surface-emitting semiconductor lasers

We describe the fabrication and operational characteristics of a novel, surface-emitting semiconductor laser that makes use of a concentric-circle grating to both define its resonant cavity and to provide surface emission. A properly fabricated circular grating causes the laser to operate in radially inward- and outward-going circular waves in the waveguide, thus, introducing the circular symmetry needed for the laser to emit a beam with a circular cross-section. The basic circular-grating-resonator concept can be implemented in any materials system; an AlGaAs/GaAs graded-index, separate confinement heterostructure (GRINSCH), single-quantum-well (SQW) semiconductor laser, grown by molecular beam epitaxy (MBE), was used for the experiments discussed here. Each concentric-circle grating was fabricated on the surface of the AlGaAs/GaAs semiconductor laser. The circular pattern was first defined by electron-beam (e-beam) lithography in a layer of polymethylmethacrylate (PMMA) and subsequently etched into the semiconductor surface using chemically-assisted (chlorine) ion-beam etching (CAIBE). We consider issues that affect the fabrication and quality of the gratings. These issues include grating design requirements, data representation of the grating pattern, and e-beam scan method. We provide examples of how these techniques can be implemented and their impact on the resulting laser performance. A comparison is made of the results obtained using two fundamentally different electron-beam writing systems. Circular gratings with period lambda = 0.25 microns and overall diameters ranging from 80 microns to 500 microns were fabricated. We also report our successful demonstration of an optically pumped, concentric-circle grating, semiconductor laser that emits a beam with a far-field divergence angle that is less than one degree. The emission spectrum is quite narrow (less than 0.1 nm) and is centered at wavelength lambda = 0.8175 microns.

Jordan, Rebecca H.↗
DOE OSTI2026

A Boundary Element Model for Assessing Large‐Scale Pressurization in Faulted Geological Storage Systems

Assessing large-scale pressurization at the regional scale—a possible outcome of large subsurface storage applications such as wastewater injection and geological carbon sequestration—presents significant computational challenges. These challenges are particularly pronounced when accounting for complex geologic structures with multiple reservoir and caprock layers, fault zones, and wells. This study introduces a computationally efficient model that integrates single-phase semi-analytical solutions with a boundary element (BE) approach. The model simulates pressure propagation in multilayered 3D systems, including vertical faults, caprock, basement, and confining units. We apply this new model to a representative scenario involving CO 2 injection near a partially sealing fault with verification against an independent two-phase flow model. Results demonstrate that our model accurately captures far-field pressure responses and that, outside the CO 2 plume zone, pressure predictions from single-phase and two-phase models are nearly identical. This supports the use of single-phase models like ours for efficient estimation of far-field pressure changes. Additionally, we demonstrate its effectiveness at a large scale, incorporating multiple wells and faults. With its ability to represent multiple wells, fault zones, and geological heterogeneity, our model is well suited for assessments of basin-scale pressurization. Its computational efficiency also makes it a promising tool for integration with optimization frameworks aimed at designing and managing injection strategies in faulted storage systems.

Cihan, A. [Lawrence Berkeley National Laboratory (↗
DOE OSTI2024

Non-resonant Bragg scattering four-wave mixing at near-visible wavelengths in low-confinement silicon nitride waveguides

Quantum state coherent frequency conversion processes—such as Bragg-scattering four-wave mixing (BSFWM)—hold promise as a flexible technique for networking heterogeneous and distant quantum systems. In this Letter, we demonstrate BSFWM within an extended (1.2-m) low-confinement silicon nitride waveguide and show that this system has the potential for near-unity frequency conversion in visible and near-visible wavelength ranges. Using sensitive classical heterodyne laser spectroscopy at low optical powers, we characterize the Kerr coefficient (∼1.55 W −1 m −1 ) and linear propagation loss (∼0.0175 dB/cm) of this non-resonant waveguide system, revealing a record-high nonlinear figure of merit (NFM = γ / α ≈ 3.85 W −1 ) for BSFWM of near-visible light in non-resonant silicon nitride waveguides. We predict how, at high yet achievable on-chip optical powers, this NFM would yield a comparatively large frequency conversion efficiency, opening the door to near-unity flexible frequency conversion without cavity enhancement and resulting bandwidth constraints.

Jaber, Nicholas (ORCID:000900070106809X)↗
NASA NTRS2019

Development of OCSS In-Suit Urine Collection and Removal System for Cabin Depressurization Scenario

NASA is developing a waste management system for use in a pressurizable space suit for future Orion missions. Driven by Orion's cabin depress operational scenario, specific life support equipment is needed for crew survival. Immediate life-sustaining resources can be provided by the Orion launch and entry suit as a pressurizable safe haven. Before long, though, the crew would also need an appropriate waste management system to maintain their crew health in a confined environment, especially over multiple days. Long-duration waste management hardware for use with a space suit has not been designed or utilized since the Apollo program, and there are numerous technical challenges associated with its implementation. In conjunction both NASA's Orion Crew Survival Systems (OCSS) and Omni Medical Systems are addressing such challenges through their on-going hardware design efforts to support future Orion missions. This paper details some of the initial design and testing efforts that have been completed while discussing the major challenges that have arisen in the process.

Harvie, Mark↗